Biology subjects

Che, Z.

Publications and source records attributed to Che, Z..

5 recordsLinked to original sources

bioRxiv2025

Magnesium isoglycyrrhizinate alleviates alcohol-associated liver disease through targeting HSD11B1

While magnesium isoglycyrrhizinate (MgIG) is a clinically approved therapy for alcohol-associated liver disease (ALD), its precise molecular targets and mechanisms remain uncharacterized. This study aimed to define MgIGs hepatoprotective actions in chronic-binge ALD mouse models and ethanol/palmitic acid-exposed AML-12 hepatocytes. Through an integrated strategy encompassing RNA sequencing, molecular docking, and microscale thermophoresis, we discovered that MgIG directly binds to hydroxysteroid 11-beta dehydrogenase 1 (HSD11B1) at residue 187, a finding corroborated by molecular dynamics simulations. In vivo, MgIG markedly attenuated alcohol-induced liver injury, evidenced by ameliorated histological damage, reduced hepatic steatosis, and normalized liver-to-body weight ratios. In vitro, it effectively reduced lipid accumulation, inflammation, and apoptosis. Mechanistically, RNA sequencing identified isopentenyl diphosphate delta isomerase 1 (IDI1) as a key downstream effector. Hepatocyte-specific genetic manipulations confirmed that MgIG modulates the SREBP2-IDI1 axis, thereby suppressing lipogenesis, inflammatory responses, and apoptotic pathways. We reveal HSD11B1 as a novel direct molecular target of MgIG and elucidate its therapeutic mechanism through the HSD11B1-SREBP2-IDI1 signaling axis, which profoundly impacts ALD pathogenesis. These findings not only validate MgIGs clinical utility but also highlight a promising new therapeutic target for ALD.

pharmacology and toxicology↗

bioRxiv2022

Distinct roles of the two SEC scaffold proteins, AFF1 and AFF4, in regulating RNA Pol II transcription elongation

The P-TEFb-containing super elongation complex (SEC) plays the essential role in transcriptional elongation control. The AF4/FMR2 family members AFF1 and AFF4 are the central scaffold proteins of SEC, associated with different human diseases. However, their specific roles in transcriptional control remain unclear. Here, we report that AFF1 and AFF4 show distinct genomic distribution patterns around TSS. AFF1 mainly binds upstream of TSS, while AFF4 is enriched downstream of TSS. Pol II occupancies are reduced genome-widely after depletion of AFF1, but not AFF4. Interestingly, in a subset of active genes with strong AFF4 binding signature, AFF4 disruption causes slow elongation and early termination, while AFF1 deletion mirrors the transcriptional defects observed in the fast Pol II mutant. Furthermore, AFF4 knockdown leads to increased AFF1 levels at chromatin, and vice versa. In summary, our data demonstrate that AFF1 and AFF4 function, to some extent, antagonistically to ensure proper Pol II transcription.

genomics↗

bioRxiv2022

Invigorating human MSCs for transplantation therapy via Nrf2/DKK1 co- stimulation in a mice acute-on-chronic liver failure model

Boosting stem cell resilience against an extrinsically harsh recipient environment is critical to therapeutic efficiency of stem cell-based transplantation innovations in liver disease contexts. We aimed to establish the efficacy of a transient plasmid-based preconditioning strategy to boost mesenchymal stromal cells (MSCs) capacity for anti-inflammation/antioxidant defense and paracrine actions on recipient hepatocytes. In MSCs, the master antioxidant regulator Nrf2 was found to bind directly to the antioxidant response element in the DKK1 promoter region. Activation of Nrf2 and DKK1 enhanced the anti-stress capacities of MSCs in vitro. In an acute-on-chronic liver failure (ACLF) murine model, transient co-overexpression of Nrf2 and DKK1 via plasmid transfection markedly improved MSC resilience against inflammatory and oxidative assaults, boosted MSC transplantation efficacy and promoted recipient liver regeneration because of a shift from the activation of the anti-regenerative IFN-{gamma}/STAT1 pathway to the pro-regenerative IL-6/STAT3 pathway in the liver. Moreover, specific ablation of DKK1 receptor CKAP4 but not LRP6 in recipient hepatocytes nullified therapeutic benefits from MSC transplantation. In long-term observations, tumorigenicity was undetected in mice following transplantation of such transiently preconditioned MCSs. In conclusion, co-stimulation of Nrf2/DKK1 signaling decisively and safely improves the efficacy of human MSC-based therapies in mouse ACLF models through apparently CKAP4-dependent paracrine mechanisms.

molecular biology↗

bioRxiv2020

RNF219 interacts with CCR4-NOT in regulating stem cell differentiation

Regulation of RNA stability plays a crucial role in gene expression control. Deadenylation is the initial rate-limiting step for the majority of RNA decay events. Here, we show that RING Finger Protein 219 (RNF219) interacts with the CCR4-NOT deadenylase complex. RNF219-CCR4-NOT exhibits deadenylation activity in vitro. RNA-seq analyses identify some of the 2-cell specific genes and the neuronal genes significantly down-regulated upon RNF219 knockdown, while up-regulated after depletion of the CCR4-NOT subunit CNOT10 in mouse embryonic stem (ES) cells. RNF219 depletion leads to impaired neuronal lineage commitment during ES cell differentiation. Our study suggests that RNF219 is a novel interacting partner of CCR4-NOT, and required for maintenance of ES cell pluripotency.View Full Text

molecular biology↗

bioRxiv2020

Learning to Control the Brain through Adaptive Closed-Loop Patterned Stimulation

Stimulation of neural activity is an important scientific and clinical tool, causally testing hypotheses and treating neurodegenerative and neuropsychiatric diseases. However, current stimulation approaches cannot flexibly control the pattern of activity in populations of neurons. To address this, we developed an adaptive, closed-loop stimulation (ACLS) system that uses patterned, multi-site electrical stimulation to control the pattern of activity in a population of neurons. Importantly, ACLS is a learning system; it monitors the response to stimulation and iteratively updates the stimulation pattern to produce a specific neural response. In silico and in vivo experiments showed ACLS quickly learns to produce specific patterns of neural activity ([~]15 minutes) and was robust to noise and drift in neural responses. In visual cortex of awake mice, ACLS learned electrical stimulation patterns that produced responses similar to the natural response evoked by visual stimuli. Similar to how repetition of a visual stimulus causes an adaptation in the neural response, the response to electrical stimulation was adapted when it was preceded by the associated visual stimulus. Altogether, our results show ACLS can learn, in real-time, to generate specific patterns of neural activity, providing a framework for using closed-loop learning to control neural activity.

neuroscience↗